W9: Invertebrate Physiology (Reproduction, Forensics & SIT) [Dr. Blair] Flashcards
(46 cards)
1
Q
Kinds of insect reproduction/Insect reproductive strategies? (3) HOP
A
- Haplodiploidy.
- Oviparous.
- Parthenogenesis.
2
Q
Haplodiploidy attributes? (3)
A
- Sexual reproduction.
- No fertilisation (haploid) (ie, eggs develop without fertilisation).
- Seen in eusocial insects (bees & ants).
3
Q
Oviparous attributes? (3)
A
- Sexual reproduction.
- Fertilisation of eggs occurs & produces diploid (2n) offspring.
- Seen in most insects (flies, mosquitoes).
4
Q
Parthenogenesis attributes? (3)
A
- Asexual reproduction.
- No fertilisation (ie, eggs develop without fertilisation).
- Seen in aphids, wasps & stick insects.
5
Q
Egs of oviparous insects? (2)
A
- Bees.
- Ants.
6
Q
Egs of parthenogenetic insects? (3)
A
- Wasps.
- Aphids.
- Stick insects.
7
Q
Eg of haplodiploidy insects?
A
Flies.
8
Q
Diptera attributes? (3)
A
- Order of flies.
- Two wings.
- Part of the important species in medical & applied entomology.
9
Q
Family under Diptera to focus on?
A
Calliphoridae.
10
Q
Calliphoridae is AKA?
A
Blow flies.
11
Q
Blow flies attributes? (2)
A
- Over 1100 species.
- Important in forensics as they often found on dead, often bloated, bodies upon which these flies/larvae are found.
12
Q
Fly life cycle layout in order? (6)
A
- Eggs.
- 1st larval stage.
- 2nd larval stage.
- 3rd larval stage.
- Pupa.
- Adult.
- Repeat process.
13
Q
Why are maggots eyes positioned where they are positioned?
A
13
Q
Blow flies courtship process: Finding Ms. Right? (5)
A
- Males will find a female (7 day old females).
- Courtship process is initiated by the male.
- Done by mating with the female and spreading her wings.
- Female’s eggs are fertilised provided she is accepting of the male.
- Females mate once, while males mate multiple times.
14
Q
Myiasis?
A
= the invasion of vertebrate tissues/organs (dead or living) by Dipteran larvae.
15
Q
Flies that cause myiasis in South Africa? (2)
A
- Tumbu flies.
- Screw-worm flies.
16
Q
Tumbu flies?
A
= under Calliphoridae family.
17
Q
Screw-worm flies attributes? (4)
A
- Under the Calliphoridae family.
- Have a rapid life cycle (3 weeks).
- Partake in obligate myiasis.
- Cause significant damage by laying eggs in vertebrate tissues, affecting livestock and sometimes humans.
18
Q
Economic impact of myiasis?
A
Infestation leads to secondary infections & significant economic losses, especially in livestock farming.
19
Q
What happens when they get into vertebrate tissue: Larvae in livestock? (4)
A
- More than just painful wounds.
- Secondary infection (death).
- Economic losses (livestock farming).
- Attracts more flies (feedback: outbreak).
20
Q
Screw-worm flies myiasis affects who? (2)
A
- Larvae in livestock.
- Larvae in humans.
21
Q
Screw-worm flies distribution attributes? (5)
A
- Severe losses to the livestock brought pressure to control/eradicate these flies (1900s-1930s).
- Pesticides & pheromone traps were unsuccessful in controlling this beast.
- Approached entomologists, Bushland & Knipling, who initiated research in 1930.
- Bushland suggested using chemicals on cattle (perhaps to make them unpalatable to the flies?).
- Knipling suggested breaking the insect life-cycle (sterile insect technique).
22
Q
Sterile Insect Technique (S.I.T)?
A
= genetic control programme that releases very high numbers of artificially sterilised males into the population, resulting in sterile matings & consequently a reduction in population size.
23
Q
S.I.T is AKA?
A
Sterile Male Release.
24
S.I.T process (lay it out for me in order)? (7)
- Mass rearing of insects.
- Sterilise males with radiation, but ensure no noticeable change (eg, sickly, etc).
- Release millions of sterile males to significantly alter the sex ration (males : females).
- Sterile males mate with wild females.
- Eggs fail to develop, leading to decreased progeny & decreased population.
- Repeat the process.
25
Did the S.I.T work?
YES, IT WORKED!
26
Explain how the S.I.T worked? (4)
- Started in Curacao in Venezuela & screw-fly populations were eliminated (7 weeks).
- Controlled in the USA (1960s-1970s).
- Eliminated in Mexico (1980s).
- Eliminated in Libya (1991).
27
What is key to the S.I.T working?
The female needs to mate once because if females mate multiple times it makes the .....
28
Forensic entomology: Role of blow flies? (3)
- Able to sense freshly dead organic matter.
- Are first to arrive (<10 mins).
- Lay egg batches.
29
Particular types of blow flies in Forensic entomology? (2)
- Green bottles.
- Blue bottles.
30
Green bottles scientific name?
Lucilia cuprina.
31
Blue bottles scientific name?
Calliphora vomitoria.
32
Green bottles attributes? (3)
- Smaller.
- Maggots.
- Compete with blue bottles for food (carrion, excreta & nectar).
33
Blue bottles attributes? (3)
- Larger.
- Maggots.
- Compete with green bottles for food (carrion, excreta & nectar).
34
Forensic entomology: In the field? (4)
Forensic entomologists:
- Collect as much data as possible such as,
- Flies, maggots & pupae.
- Ambient weather conditions (temperature affects the rate of development of flies).
- Position of the body (outdoors, shade, buried).
35
Forensic entomology: In the lab? (3)
Forensic entomologists:
- Determine the developmental stage & species collected from the field.
- Calculate the development rate of the stages.
- Data are compared against weather conditions to estimate the time of oviposition (Post Mortem Interval).
36
Explain the graph of Temperature & fly development? (9)
- Graph illustrates the importance of temperature for fly development from an egg to adult.
- x-axis = Temperature.
- y-axis = Developmental time (days).
- Flies fail to develop at 10-13 degrees celsius.
- As temperature increases, the developmental time decreases exponentially from egg to adult.
- At 20C, eggs take about 25 days to develop into an adult & that decreases as it develops into an adult with increasing temperature.
- At 25C, it took about 15 days to develop from egg to adult.
- At 30C, it took about 12 days to develop from egg to adult.
- At 35C, it took 10 days to develop from egg to adult.
37
PMI stands for?
Post Mortem Interval.
38
Forensic entomology: PMI? (2)
- PMI graph.
- Forensic entomologists work backwards when determining the PMI.
39
Explain the PMI graph?
40
Forensic entomology: Added benefits from flies? (4)
- Locality, through the potential movement of the victim or locality of their death (eg, dumping).
- Trauma, through the presence & abundance of maggots within a corpse being used as a trauma guide.
- Toxins, through flies/maggots being examined for the presence of drugs/toxins (entomotoxicology).
- DNA identification, through the fact that maggots feeding on a corpse may retain testable DNA.
41
Types of entomology covered? (2)
- Forensic entomology.
- Medical entomology.
42
Medical entomology: Benefits from flies?
Sterilised blow flies, particularly green bottles, are used in Maggot therapy.
43
Maggot therapy?
= where sterilised blow flies, especially green bottles, are used in medicine to help clean wounds by removing dead tissue, promoting healing & reducing infection.
44
Maggot therapy benefits? (3)
- Aid in removal of damaged tissue.
- Regeneration of new cells.
- Decreasing infection by microbes.
45
Super summary? (3)
- Reproduction (majority of insects are oviparous, asexual reproduction is possible in some).
- Life cycle (understanding the reproductive cycle, larva to adult).
- Useful applications (sterile insect technique, forensic entomology, medical uses via maggot therapy).
